An economic brawl has erupted between Labor and the Coalition, with both sides accusing the other of costings blowouts and errors in their election spending promises. Both sides of politics have promised to offset their election spending with cuts made in other areas. The Coalition says Labor has a $3.4 billion black hole in its spending commitments but Labor has accused the Coalition of confusion over its spending figures and dodging scrutiny of its costings. Labor has also seized on a report in Fairfax newspapers today which says that the Coalition has overestimated $800 million in budget savings from ditching the National Broadband Network. Treasurer Wayne Swan has rejected Opposition calculations released last night which claim to show that Labor has a black hole in its own costings. "It's an attempt to say that Labor is spending more than we say, but it gets it all wrong," he said. "They're counting an item that's $1.5 million at $15 million. There's confusion, there is double counting." Mr Swan has seized on the report of the Coalition's $800m error and says it must submit all of its spending promises to the Treasury immediately. "I think they've put in about 1.5 per cent of those spending commitments," he told 2UE "They have now $27 billion worth of spending commitments which they have not submitted to the Treasury finance process for detailed scrutiny. "I think that they are having a lot of trouble making their numbers add up, and what that does is threaten the surplus." Opposition Treasury spokesman Joe Hockey says all promises will be submitted but he will not say when. "Before every election there's this to and fro about costings," he told Radio National. And he has dismissed reports of an $800m overestimation in savings. "This is a secret Treasury document the journalist is quoting from," he said."They go and have a secret Treasury analysis. We don't know what the secret Treasury analysis is." Mr Hockey has also hosed down accusations he and Mr Abbott are at odds over the amount of the Coalition's spending commitments after both appeared yesterday to cite different figures.